1. Field of the Invention
The present invention relates to a radio receiver and, more particularly, to a low-power-consumption radio receiver which can receive a plurality of different channel frequencies and can reduce power consumption.
2. Description of the Prior Art
Various radio receivers such as portable telephones and mobile computers have been proposed. Recently, a software radio system has been proposed and developed.
This software radio system is characterized in that the same device can perform communications at different frequencies or by different communication schemes by making software changes.
A reduction in power consumption presents a significant challenge to a radio receiver, and more specifically, a portable radio receiver, and demands have arisen for the development of low-power consumption radio receiver.
The present invention has been made in consideration of the above situation in the prior art, and has as its object to provide a low-power-consumption radio receiver which reduces power consumption by decreasing the data rate of reception data.
In order to achieve the above object, according to the first aspect of the present invention, there is provided a radio receiver comprising a device for decreasing a data rate of reception data in accordance with a channel frequency of the reception data, and a device for performing signal processing for the reception data whose data rate has been decreased.
According to the second aspect of the present invention, there is provided a radio receiver capable of receiving a plurality of different channel frequencies, comprising an A/D converter for A/D-converting a reception signal, a signal processing section for performing digital signal processing for a signal having undergone digital conversion in the A/D converter, and a sampling frequency changing device for changing a sampling frequency in the A/D converter in accordance with a frequency of the reception signal, or a data rate changing device for changing a data rate of the signal input to the signal processing section and having undergone digital conversion.
According to the third aspect of the present invention, there is provided a power consumption reducing method in a radio receiver, comprising the steps of decreasing a data rate of reception data, and performing signal processing for the reception data whose data rate has been decreased.
Power consumption poses a significant challenge to portable telephones, mobile computers, and the like. It is known that power consumption can be reduced in signal processing by decreasing the clock used for the processing. In the present invention, the clock required for signal processing is decreased by decreasing the data rate, thereby realizing a power consumption reducing effect.